murphy



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(No Model.)

- B MURPHY SEWING MACHINE.

N0.'554,626. Pate'nt'edPeb. 11,1896.

' (No Model.) 3 Sheets-Sheet 2.

' E MURPHY SEWING MACHINE.

No. 554,626. Patented Feb. .11,

(No Model.) 3 Slieets-Sheet 3. E. MURPHY.

. SEWING MACHINE .NO. 554,626. v I Patented Feb. 11, 1896.

g i k "ml 29 Nl'lED TATES FFICEQ EDlVARD MURPHY, OF NEW YORK, N. Y.

SEWING-MACHINE.

SPECIFICATION forming part of Letters Patent No. 554,626, dated February11, 1896.

Application filed July 13, 1895. $erial No. 555,888. (No model.)

To aZZ whom it may concern.-

Be it known that I, EDWARD MURPHY, a citizen of the United States,residing at New York, in the county of New York and State of New York,have invented new and useful Improvements in Sewing-Machines, of whichthe following is a specification.

This invention relates to that class of sewing-machines which areemployed to form an elastic double-loop or chain stitch in the sewing ofknit goods and elastic fabrics.

One of the principal objects of my improvements is to provide a simple,reliable, and positively-actuated take-up device to control the lowerthread with certainty and in perfect accord with.the movements of thelooper, and yet so that the said lower thread will be sufficiently freeto permit a very rapid running of the machine without liability tobreakage of the thread from sudden strain.

It is a further purpose of my invention to provide an improvedconnection between the needle-bar and its actuating-arm, whereby theneedle-bar may be caused to have a perfectlyvertical reciprocationwithout tendency to lateral oscillation or binding in its supports, andso that a suitable play will be afforded at the point of connectionbetween the needlebar and needle-arm.

The feed devices, the looper and their actuating mechanisms may be ofthe construction and character described in Letters Patent No. 525,227,granted to me August 28, 1894..

My present invention consists in the features of construction and novelcombinations of parts in a double-chain stitch sewing-machine, ashereinafter set forth and claimed.

In the annexed drawings,illustrating the in vention, Figure 1 is a sideelevation of a sewing-machine embodying my improvements. Fig. 2 is aplan of the same, with parts in section. Fig. 3 is a rear end elevationof the machine, with parts broken away. Fig. 4 is ahorizontally-sectional detail view of the positively-actuatedintermittent tension for the lower thread. Fig. 5 is a detail view ofthe take-up for the lower thread. Fig. 6 is a detail view of thetrimming mechanism. Fig. 7 is a sectional detail view of the device forconnecting the vertically-reciprocating needle-bar and oscillatoryneedle-arm.

Referring to the several parts of the drawings in detail, the numeral 1designates a suitable frame or base supporting the usual overhanging armor goose-neck 2, the forward end of which is provided with the usualguides for a vertically-movable presser-bar 3 and avertically-reciprocating needle-bar 4. To the lower end of thepresser-bar 3 is attached a presser-foot 5 of ordinary construction.

The needle-bar 4 carries a needle 6 and is reciprocated vertically bymeans of an oscillatory needle arm or lever 7 fulcrumed to the rearportion of the goose-neck by a pivot 8, as usual. The needle arm orlever 7 is oscillated in the usual manner through a pitman 9 connectingwith an eccentric on the main driving-shaft 10, that is journaled orsupported in the frame of the machine in any suitable or ordinarymanner.

In order that the needle-bar 4 may be caused to reciprocate in a truevertical path without liability to oscillation or binding in its guides,there is placed on the needle-bar a sleeve 11, having projecting fromits rear side a wristpin 12, through which there is passedlongitudinally a set-screw 13, the inner end of which bites into a notchor slight depression formed in the needle-bar, so as to hold the sleeve11 firmly thereon. The wrist-pin 12 supports a longitudinally-slidingsleeve 14, from one side of which projects a wrist-pin 15, engaging aneye in the forward end of the oscillatory needle-arm 7, and by thissimple construction a sufficient play is provided in the connectionsbetween the needle-bar and needle-arm to cause the needle-bar to have aperfectly true vertical movement without any tendency to wobbling orbinding.

The feed devices employed in this machine may be of the sameconstruction and character as described in my before-named patent, No.525,227. As shown, the feed-dog carrying-bar 16 is connected with andreciprocated from a yoke 17, mounted on a rock-shaft 18, having on itsrear end an upright slotted arm 19, that is adj ustably connectedwith-the outer end of a link 20, the inner end of which engages aneccentric on the driving-shaft 10, from which the feed is actuated.

A vibratory looper 21 may be employed of the character shown anddescribed in my said former Patent No. 525,227, and is preferablyoperated from the shaft 10 by the mechanism described in said patent andmay be so arranged as to be conveniently swung in a horizontal plane toplace its eye or point beyond or outside one edge of the work-plate tofacilitate threading. As the needle 6 rises, the looper 21 moves inwardinto the loop of the needle-thread and laterally to one side of the pathin which the needle traverses, and as the needle descends the loopermoves outward and laterally to the opposite side of the needle-path forproducing the required doubleloop or chain stitch. The manner of mounting and operating the four-motion looper and its arrangement with relationto a four-motion feed are fully described in my aforesaid former patent.

On the rear portion of the goose-neck 2 is supported atransversely-arranged sleeve 22, from within one end of which isextended a laterally-proj ecting and lon gitudinally-reciprocatingspindle 23, having two parallel arranged tension disks 21L and 25loosely mounted thereon. The spindle 23 is surrounded outside thetension-disks by a spirally-coiled spring 26, held in place by a nut 27on the outer end of the spindle, the said nut forming a bearin g for oneend of the spring 26, that bears at its other end against the outermosttension-disk.

In the rear side of the transversely-arranged sleeve 22 is an opening 28for passage'of a pin or stud 29, connecting the reciprocating spin dle23 with the upper end of a two -armed lever 30, fulcrumed to the rear ofthe gooseneck at a point below the sleeve 22 thereon. The lower arm ofthe lever 30 is provided with a longitudinal slot 31, loosely engaging apin 2, carried on the cap or head of the pitman 9 that connects with themain drive-shaft. Through the movements of the pitman 9 in actuating theneedle-arm '7 an intermittent oscillation is imparted through thepin-andslot connection to the lever 30, which in turn reciprocates thespindle 23 and attached nut 27, so as to cause the spring-pressed outerdisk 25 to exert, with the inner stationary disk 24, an intermittenttension upon the lower or looper thread, a, that is passed between saiddisks. For the upper or needle thread, I), there may be arranged on oneend of the sleeve 22 or elsewhere a tension device 34: of any suitablekind. Above the tension devices for the lower and upper threads arearranged guides 35 and 36, through which the said threads are passedfrom their respective spools.

It is important that the slack in the lower thread, caused by recedingmovements of the looper, should be taken up promptly and with certaintythrough positively-actuated mechanism operating in unison with thelooper movements and so that the looper-thread will not be subjected tosudden or undue strain even when the machine is operated at a highspeed. For this purpose there is preferably connected with the lower endof the pitman 9 a laterally-projecting arm 37, that partakes of themovements of the eccentric from which the pitman is actuated. On theouter end of the arm 37 there is carried a take-up 38, consisting of arod that is first extended in a forward direction, then outward from itsforward portion, and then upward on the outer side of the path of thelooper-thread a, the said looper-thread being carried downward from theintermittent tension-disks 2i and 25 and through thread eyes or guides39 and 40 placed on opposite sides of the outward laterallyprojectingarm of the said take-up and above the path in which it moves. The saidtake-up 38 is thus arranged to operate below and at the outer side ofthe path of the looper-thread.

Instead of being carried by and operated from an arm supported by thepitman J the take-up might obviously be carried by an arm actuated froman eccentric on the main shaft other than the eccentric that operatesthe pitman, but the construction shown is preferable for compactness andsimplicity of arrangement.

It will be observed that the vertical arm of the take-up 38 is formedwith a slight crook that provides a shoulder 41 on its inner side. Intaking up the slack of the looper-thread the vertical arm of the take-up38 moves downward, then inward, and engages the thread at or about thetake-up shoulder 41. The inward movement of the shouldered take-up armis then continued slightly and then changes to an upward movement,carrying the thread, meanwhile, upon the shoulder 41, thereby taking upthe slack, and, finally, as the upward movement of the take-up stillcontinues it is moved also outward so as to throw off the thread as itis required by the looper. In its operation upon the looperthread thetake-up 38 acts gradually and smoothly, without sudden strain that wouldbe liable to snap the thread, and being positively actuated from theeccentric on the main shaft and in time movements with the looper it isobvious that the control of the lower thread will be always certain,regardless of the speed of the machine.

In work of the character for which this 1na chine is more particularlydesigned it is desirable to provide shearing mechanism for trimming thesurplus fabric beyond the line of stitching. To this end there isprovided in the cloth-plate 42 a suitable recess for reception of ahorizontally-arrangod and stationary lower cutting-blade 43, that isremovably secured in place by a clamping-plate ii and nut 45, as shown.The upper and movable cutting-blade, 46, is arranged to oscillate in avertical direction adjacent to the cuttingedge of the lower blade. Thisupper blade, 46, is adjustably supported 011 and carried by an arm 47,mounted on the forward end of a rock-shaft 4S, journaled in bearings at49 and 50 above the cloth plate or bed. One end of the rock-shaft 48 isprovided with an arm 51, connected by a link or pitman 52 with ancecentric on the main drive-shaft from which the trimming mechanism isactuated in accord with the movements of the feeding and stitchingdevices. A brace-rod 53 may be arranged to connect the rock-shaftbearings 49 and 50 at the forward and rear ends of the goose-neck oroverhanging frame-arm 2, so that the shearing mechanism may be made tooperate with great steadiness and without straining the frame.

This machine is particularly adapted for factory work where greataccuracy and high speed are required; but the machine is also desirablefor family use. By reason of the simple and compact arrangement of itsseveral parts and the consequent ability to shorten the variousconnecting-shafts and levers of the operating mechanisms, and thefacility with which the several bearings and connections may behardened, it will be ob vious that the machine may be run at a very highspeed without impairing its durability or efficiency.

\Vhat I claim as my invention is- 1. In a double -chain-stitchsewing-machine, the combination-with the needle, the looper and the maindriving-shaft, of a positivelyactuated take-up, for the lower thread,consisting of an arm actuated from an eccentric 011 the maindriving-shaft and a rod carried by said arm and extended therefromforward, outward below and upward to the outside of the path of thelower thread, the said upward extended arm of the take-up being providedwith a shoulder to engage the said thread, and thread-guides whichdetermine the path of the thread located on opposite sides of the saidtake-up, substantially as described.

2. In a double-chain-stitch sewing-machine, the combination with thestitch forming mechanism, and a pair of guides to determine the path ofthe lower thread, of a take-up for the lower thread consisting of avibratory rod positively actuated from a moving part of the machine andextended outward and upward between the said thread-guides and below andto the outside of the path of the lower thread, the upward extended armof said take-up rod being provided with a projection or shoulder andthereby adapted to act gradually and smoothly on the lower thread totake up the slack at required intervals, substantially as described.

3. In a double-chain-stitch' sewing-machine, the combination with theneedle and looper and their operating mechanisms, of apositively-actuated take-up carried on the pitman of theneedle-operating mechanism and consistin g of a forward, outward andupward extended rod having on the inner side of its .upward extendedportion a shoulder adapted to engage the lower thread and take up theslack, and thread-guides located on opposite sides of the outward andupward extended portions of the take-up, substantially as described.

4. In a double-chain-stitch sewing-machine, the combination with theneedle. and looper and their operating mechanisms, of apositively-actuated intermittent tension device for the lower thread,and a positively-actuated take-up, for the said lower thread, carried ona portion of the needleoperating mechanism and comprising a forward,outward and upward extended rod or arm having a shoulder to engage andrelease the said lower thread at required intervals, .and thread-guideslocated on opposite sides of the said take-up, substantially asdescribed.

5. In a sewing-machine, the combination with a vertically-reciprocatingneedle-bar, and an oscillatory needle arm or lever having an eye in itsforward end, of a sleeve mounted on the needle-bar and provided with arearward projecting wrist-pin, a set-screw passed longitudinally throughsaid wrist-pin to engage the needle bar, and a sliding sleeve mounted onsaid rearward projecting wristpin and provided with alaterally-projecting wrist-pin engaging the eye in the forward end ofthe needle-arm, substantially as described.

In testimony whereof I have hereunto set my hand in presence of twosubscribing wit- I nesses.

